diff -r 57875cf423c9 -r 2372284d9457 contrib/check-code.py
--- a/contrib/check-code.py	Sat Oct 05 10:29:34 2019 -0400
+++ b/contrib/check-code.py	Sun Oct 06 09:45:02 2019 -0400
@@ -26,11 +26,15 @@
 import os
 import re
 import sys
+
 if sys.version_info[0] < 3:
     opentext = open
 else:
+
     def opentext(f):
         return open(f, encoding='latin1')
+
+
 try:
     xrange
 except NameError:
@@ -42,6 +46,7 @@
 
 import testparseutil
 
+
 def compilere(pat, multiline=False):
     if multiline:
         pat = '(?m)' + pat
@@ -52,10 +57,22 @@
             pass
     return re.compile(pat)
 
+
 # check "rules depending on implementation of repquote()" in each
 # patterns (especially pypats), before changing around repquote()
-_repquotefixedmap = {' ': ' ', '\n': '\n', '.': 'p', ':': 'q',
-                     '%': '%', '\\': 'b', '*': 'A', '+': 'P', '-': 'M'}
+_repquotefixedmap = {
+    ' ': ' ',
+    '\n': '\n',
+    '.': 'p',
+    ':': 'q',
+    '%': '%',
+    '\\': 'b',
+    '*': 'A',
+    '+': 'P',
+    '-': 'M',
+}
+
+
 def _repquoteencodechr(i):
     if i > 255:
         return 'u'
@@ -67,13 +84,17 @@
     if c.isdigit():
         return 'n'
     return 'o'
+
+
 _repquotett = ''.join(_repquoteencodechr(i) for i in xrange(256))
 
+
 def repquote(m):
     t = m.group('text')
     t = t.translate(_repquotett)
     return m.group('quote') + t + m.group('quote')
 
+
 def reppython(m):
     comment = m.group('comment')
     if comment:
@@ -81,86 +102,103 @@
         return "#" * l + comment[l:]
     return repquote(m)
 
+
 def repcomment(m):
     return m.group(1) + "#" * len(m.group(2))
 
+
 def repccomment(m):
     t = re.sub(r"((?<=\n) )|\S", "x", m.group(2))
     return m.group(1) + t + "*/"
 
+
 def repcallspaces(m):
     t = re.sub(r"\n\s+", "\n", m.group(2))
     return m.group(1) + t
 
+
 def repinclude(m):
     return m.group(1) + "<foo>"
 
+
 def rephere(m):
     t = re.sub(r"\S", "x", m.group(2))
     return m.group(1) + t
 
 
 testpats = [
-  [
-    (r'\b(push|pop)d\b', "don't use 'pushd' or 'popd', use 'cd'"),
-    (r'\W\$?\(\([^\)\n]*\)\)', "don't use (()) or $(()), use 'expr'"),
-    (r'grep.*-q', "don't use 'grep -q', redirect to /dev/null"),
-    (r'(?<!hg )grep.* -a', "don't use 'grep -a', use in-line python"),
-    (r'sed.*-i', "don't use 'sed -i', use a temporary file"),
-    (r'\becho\b.*\\n', "don't use 'echo \\n', use printf"),
-    (r'echo -n', "don't use 'echo -n', use printf"),
-    (r'(^|\|\s*)\bwc\b[^|]*$\n(?!.*\(re\))', "filter wc output"),
-    (r'head -c', "don't use 'head -c', use 'dd'"),
-    (r'tail -n', "don't use the '-n' option to tail, just use '-<num>'"),
-    (r'sha1sum', "don't use sha1sum, use $TESTDIR/md5sum.py"),
-    (r'\bls\b.*-\w*R', "don't use 'ls -R', use 'find'"),
-    (r'printf.*[^\\]\\([1-9]|0\d)', r"don't use 'printf \NNN', use Python"),
-    (r'printf.*[^\\]\\x', "don't use printf \\x, use Python"),
-    (r'rm -rf \*', "don't use naked rm -rf, target a directory"),
-    (r'\[[^\]]+==', '[ foo == bar ] is a bashism, use [ foo = bar ] instead'),
-    (r'(^|\|\s*)grep (-\w\s+)*[^|]*[(|]\w',
-     "use egrep for extended grep syntax"),
-    (r'(^|\|\s*)e?grep .*\\S', "don't use \\S in regular expression"),
-    (r'(?<!!)/bin/', "don't use explicit paths for tools"),
-    (r'#!.*/bash', "don't use bash in shebang, use sh"),
-    (r'[^\n]\Z', "no trailing newline"),
-    (r'export .*=', "don't export and assign at once"),
-    (r'^source\b', "don't use 'source', use '.'"),
-    (r'touch -d', "don't use 'touch -d', use 'touch -t' instead"),
-    (r'\bls +[^|\n-]+ +-', "options to 'ls' must come before filenames"),
-    (r'[^>\n]>\s*\$HGRCPATH', "don't overwrite $HGRCPATH, append to it"),
-    (r'^stop\(\)', "don't use 'stop' as a shell function name"),
-    (r'(\[|\btest\b).*-e ', "don't use 'test -e', use 'test -f'"),
-    (r'\[\[\s+[^\]]*\]\]', "don't use '[[ ]]', use '[ ]'"),
-    (r'^alias\b.*=', "don't use alias, use a function"),
-    (r'if\s*!', "don't use '!' to negate exit status"),
-    (r'/dev/u?random', "don't use entropy, use /dev/zero"),
-    (r'do\s*true;\s*done', "don't use true as loop body, use sleep 0"),
-    (r'sed (-e )?\'(\d+|/[^/]*/)i(?!\\\n)',
-     "put a backslash-escaped newline after sed 'i' command"),
-    (r'^diff *-\w*[uU].*$\n(^  \$ |^$)', "prefix diff -u/-U with cmp"),
-    (r'^\s+(if)? diff *-\w*[uU]', "prefix diff -u/-U with cmp"),
-    (r'[\s="`\']python\s(?!bindings)', "don't use 'python', use '$PYTHON'"),
-    (r'seq ', "don't use 'seq', use $TESTDIR/seq.py"),
-    (r'\butil\.Abort\b', "directly use error.Abort"),
-    (r'\|&', "don't use |&, use 2>&1"),
-    (r'\w =  +\w', "only one space after = allowed"),
-    (r'\bsed\b.*[^\\]\\n', "don't use 'sed ... \\n', use a \\ and a newline"),
-    (r'env.*-u', "don't use 'env -u VAR', use 'unset VAR'"),
-    (r'cp.* -r ', "don't use 'cp -r', use 'cp -R'"),
-    (r'grep.* -[ABC]', "don't use grep's context flags"),
-    (r'find.*-printf',
-     "don't use 'find -printf', it doesn't exist on BSD find(1)"),
-    (r'\$RANDOM ', "don't use bash-only $RANDOM to generate random values"),
-  ],
-  # warnings
-  [
-    (r'^function', "don't use 'function', use old style"),
-    (r'^diff.*-\w*N', "don't use 'diff -N'"),
-    (r'\$PWD|\${PWD}', "don't use $PWD, use `pwd`"),
-    (r'^([^"\'\n]|("[^"\n]*")|(\'[^\'\n]*\'))*\^', "^ must be quoted"),
-    (r'kill (`|\$\()', "don't use kill, use killdaemons.py")
-  ]
+    [
+        (r'\b(push|pop)d\b', "don't use 'pushd' or 'popd', use 'cd'"),
+        (r'\W\$?\(\([^\)\n]*\)\)', "don't use (()) or $(()), use 'expr'"),
+        (r'grep.*-q', "don't use 'grep -q', redirect to /dev/null"),
+        (r'(?<!hg )grep.* -a', "don't use 'grep -a', use in-line python"),
+        (r'sed.*-i', "don't use 'sed -i', use a temporary file"),
+        (r'\becho\b.*\\n', "don't use 'echo \\n', use printf"),
+        (r'echo -n', "don't use 'echo -n', use printf"),
+        (r'(^|\|\s*)\bwc\b[^|]*$\n(?!.*\(re\))', "filter wc output"),
+        (r'head -c', "don't use 'head -c', use 'dd'"),
+        (r'tail -n', "don't use the '-n' option to tail, just use '-<num>'"),
+        (r'sha1sum', "don't use sha1sum, use $TESTDIR/md5sum.py"),
+        (r'\bls\b.*-\w*R', "don't use 'ls -R', use 'find'"),
+        (r'printf.*[^\\]\\([1-9]|0\d)', r"don't use 'printf \NNN', use Python"),
+        (r'printf.*[^\\]\\x', "don't use printf \\x, use Python"),
+        (r'rm -rf \*', "don't use naked rm -rf, target a directory"),
+        (
+            r'\[[^\]]+==',
+            '[ foo == bar ] is a bashism, use [ foo = bar ] instead',
+        ),
+        (
+            r'(^|\|\s*)grep (-\w\s+)*[^|]*[(|]\w',
+            "use egrep for extended grep syntax",
+        ),
+        (r'(^|\|\s*)e?grep .*\\S', "don't use \\S in regular expression"),
+        (r'(?<!!)/bin/', "don't use explicit paths for tools"),
+        (r'#!.*/bash', "don't use bash in shebang, use sh"),
+        (r'[^\n]\Z', "no trailing newline"),
+        (r'export .*=', "don't export and assign at once"),
+        (r'^source\b', "don't use 'source', use '.'"),
+        (r'touch -d', "don't use 'touch -d', use 'touch -t' instead"),
+        (r'\bls +[^|\n-]+ +-', "options to 'ls' must come before filenames"),
+        (r'[^>\n]>\s*\$HGRCPATH', "don't overwrite $HGRCPATH, append to it"),
+        (r'^stop\(\)', "don't use 'stop' as a shell function name"),
+        (r'(\[|\btest\b).*-e ', "don't use 'test -e', use 'test -f'"),
+        (r'\[\[\s+[^\]]*\]\]', "don't use '[[ ]]', use '[ ]'"),
+        (r'^alias\b.*=', "don't use alias, use a function"),
+        (r'if\s*!', "don't use '!' to negate exit status"),
+        (r'/dev/u?random', "don't use entropy, use /dev/zero"),
+        (r'do\s*true;\s*done', "don't use true as loop body, use sleep 0"),
+        (
+            r'sed (-e )?\'(\d+|/[^/]*/)i(?!\\\n)',
+            "put a backslash-escaped newline after sed 'i' command",
+        ),
+        (r'^diff *-\w*[uU].*$\n(^  \$ |^$)', "prefix diff -u/-U with cmp"),
+        (r'^\s+(if)? diff *-\w*[uU]', "prefix diff -u/-U with cmp"),
+        (r'[\s="`\']python\s(?!bindings)', "don't use 'python', use '$PYTHON'"),
+        (r'seq ', "don't use 'seq', use $TESTDIR/seq.py"),
+        (r'\butil\.Abort\b', "directly use error.Abort"),
+        (r'\|&', "don't use |&, use 2>&1"),
+        (r'\w =  +\w', "only one space after = allowed"),
+        (
+            r'\bsed\b.*[^\\]\\n',
+            "don't use 'sed ... \\n', use a \\ and a newline",
+        ),
+        (r'env.*-u', "don't use 'env -u VAR', use 'unset VAR'"),
+        (r'cp.* -r ', "don't use 'cp -r', use 'cp -R'"),
+        (r'grep.* -[ABC]', "don't use grep's context flags"),
+        (
+            r'find.*-printf',
+            "don't use 'find -printf', it doesn't exist on BSD find(1)",
+        ),
+        (r'\$RANDOM ', "don't use bash-only $RANDOM to generate random values"),
+    ],
+    # warnings
+    [
+        (r'^function', "don't use 'function', use old style"),
+        (r'^diff.*-\w*N', "don't use 'diff -N'"),
+        (r'\$PWD|\${PWD}', "don't use $PWD, use `pwd`"),
+        (r'^([^"\'\n]|("[^"\n]*")|(\'[^\'\n]*\'))*\^', "^ must be quoted"),
+        (r'kill (`|\$\()', "don't use kill, use killdaemons.py"),
+    ],
 ]
 
 testfilters = [
@@ -170,45 +208,72 @@
 
 uprefix = r"^  \$ "
 utestpats = [
-  [
-    (r'^(\S.*||  [$>] \S.*)[ \t]\n', "trailing whitespace on non-output"),
-    (uprefix + r'.*\|\s*sed[^|>\n]*\n',
-     "use regex test output patterns instead of sed"),
-    (uprefix + r'(true|exit 0)', "explicit zero exit unnecessary"),
-    (uprefix + r'.*(?<!\[)\$\?', "explicit exit code checks unnecessary"),
-    (uprefix + r'.*\|\| echo.*(fail|error)',
-     "explicit exit code checks unnecessary"),
-    (uprefix + r'set -e', "don't use set -e"),
-    (uprefix + r'(\s|fi\b|done\b)', "use > for continued lines"),
-    (uprefix + r'.*:\.\S*/', "x:.y in a path does not work on msys, rewrite "
-     "as x://.y, or see `hg log -k msys` for alternatives", r'-\S+:\.|' #-Rxxx
-     '# no-msys'), # in test-pull.t which is skipped on windows
-    (r'^  [^$>].*27\.0\.0\.1',
-     'use $LOCALIP not an explicit loopback address'),
-    (r'^  (?![>$] ).*\$LOCALIP.*[^)]$',
-     'mark $LOCALIP output lines with (glob) to help tests in BSD jails'),
-    (r'^  (cat|find): .*: \$ENOENT\$',
-     'use test -f to test for file existence'),
-    (r'^  diff -[^ -]*p',
-     "don't use (external) diff with -p for portability"),
-    (r' readlink ', 'use readlink.py instead of readlink'),
-    (r'^  [-+][-+][-+] .* [-+]0000 \(glob\)',
-     "glob timezone field in diff output for portability"),
-    (r'^  @@ -[0-9]+ [+][0-9]+,[0-9]+ @@',
-     "use '@@ -N* +N,n @@ (glob)' style chunk header for portability"),
-    (r'^  @@ -[0-9]+,[0-9]+ [+][0-9]+ @@',
-     "use '@@ -N,n +N* @@ (glob)' style chunk header for portability"),
-    (r'^  @@ -[0-9]+ [+][0-9]+ @@',
-     "use '@@ -N* +N* @@ (glob)' style chunk header for portability"),
-    (uprefix + r'hg( +-[^ ]+( +[^ ]+)?)* +extdiff'
-     r'( +(-[^ po-]+|--(?!program|option)[^ ]+|[^-][^ ]*))*$',
-     "use $RUNTESTDIR/pdiff via extdiff (or -o/-p for false-positives)"),
-  ],
-  # warnings
-  [
-    (r'^  (?!.*\$LOCALIP)[^*?/\n]* \(glob\)$',
-     "glob match with no glob string (?, *, /, and $LOCALIP)"),
-  ]
+    [
+        (r'^(\S.*||  [$>] \S.*)[ \t]\n', "trailing whitespace on non-output"),
+        (
+            uprefix + r'.*\|\s*sed[^|>\n]*\n',
+            "use regex test output patterns instead of sed",
+        ),
+        (uprefix + r'(true|exit 0)', "explicit zero exit unnecessary"),
+        (uprefix + r'.*(?<!\[)\$\?', "explicit exit code checks unnecessary"),
+        (
+            uprefix + r'.*\|\| echo.*(fail|error)',
+            "explicit exit code checks unnecessary",
+        ),
+        (uprefix + r'set -e', "don't use set -e"),
+        (uprefix + r'(\s|fi\b|done\b)', "use > for continued lines"),
+        (
+            uprefix + r'.*:\.\S*/',
+            "x:.y in a path does not work on msys, rewrite "
+            "as x://.y, or see `hg log -k msys` for alternatives",
+            r'-\S+:\.|' '# no-msys',  # -Rxxx
+        ),  # in test-pull.t which is skipped on windows
+        (
+            r'^  [^$>].*27\.0\.0\.1',
+            'use $LOCALIP not an explicit loopback address',
+        ),
+        (
+            r'^  (?![>$] ).*\$LOCALIP.*[^)]$',
+            'mark $LOCALIP output lines with (glob) to help tests in BSD jails',
+        ),
+        (
+            r'^  (cat|find): .*: \$ENOENT\$',
+            'use test -f to test for file existence',
+        ),
+        (
+            r'^  diff -[^ -]*p',
+            "don't use (external) diff with -p for portability",
+        ),
+        (r' readlink ', 'use readlink.py instead of readlink'),
+        (
+            r'^  [-+][-+][-+] .* [-+]0000 \(glob\)',
+            "glob timezone field in diff output for portability",
+        ),
+        (
+            r'^  @@ -[0-9]+ [+][0-9]+,[0-9]+ @@',
+            "use '@@ -N* +N,n @@ (glob)' style chunk header for portability",
+        ),
+        (
+            r'^  @@ -[0-9]+,[0-9]+ [+][0-9]+ @@',
+            "use '@@ -N,n +N* @@ (glob)' style chunk header for portability",
+        ),
+        (
+            r'^  @@ -[0-9]+ [+][0-9]+ @@',
+            "use '@@ -N* +N* @@ (glob)' style chunk header for portability",
+        ),
+        (
+            uprefix + r'hg( +-[^ ]+( +[^ ]+)?)* +extdiff'
+            r'( +(-[^ po-]+|--(?!program|option)[^ ]+|[^-][^ ]*))*$',
+            "use $RUNTESTDIR/pdiff via extdiff (or -o/-p for false-positives)",
+        ),
+    ],
+    # warnings
+    [
+        (
+            r'^  (?!.*\$LOCALIP)[^*?/\n]* \(glob\)$',
+            "glob match with no glob string (?, *, /, and $LOCALIP)",
+        ),
+    ],
 ]
 
 # transform plain test rules to unified test's
@@ -234,148 +299,212 @@
 
 # common patterns to check *.py
 commonpypats = [
-  [
-    (r'\\$', 'Use () to wrap long lines in Python, not \\'),
-    (r'^\s*def\s*\w+\s*\(.*,\s*\(',
-     "tuple parameter unpacking not available in Python 3+"),
-    (r'lambda\s*\(.*,.*\)',
-     "tuple parameter unpacking not available in Python 3+"),
-    (r'(?<!def)\s+(cmp)\(', "cmp is not available in Python 3+"),
-    (r'(?<!\.)\breduce\s*\(.*', "reduce is not available in Python 3+"),
-    (r'\bdict\(.*=', 'dict() is different in Py2 and 3 and is slower than {}',
-     'dict-from-generator'),
-    (r'\.has_key\b', "dict.has_key is not available in Python 3+"),
-    (r'\s<>\s', '<> operator is not available in Python 3+, use !='),
-    (r'^\s*\t', "don't use tabs"),
-    (r'\S;\s*\n', "semicolon"),
-    (r'[^_]_\([ \t\n]*(?:"[^"]+"[ \t\n+]*)+%', "don't use % inside _()"),
-    (r"[^_]_\([ \t\n]*(?:'[^']+'[ \t\n+]*)+%", "don't use % inside _()"),
-    (r'(\w|\)),\w', "missing whitespace after ,"),
-    (r'(\w|\))[+/*\-<>]\w', "missing whitespace in expression"),
-    (r'\w\s=\s\s+\w', "gratuitous whitespace after ="),
-    ((
-        # a line ending with a colon, potentially with trailing comments
-        r':([ \t]*#[^\n]*)?\n'
-        # one that is not a pass and not only a comment
-        r'(?P<indent>[ \t]+)[^#][^\n]+\n'
-        # more lines at the same indent level
-        r'((?P=indent)[^\n]+\n)*'
-        # a pass at the same indent level, which is bogus
-        r'(?P=indent)pass[ \t\n#]'
-      ), 'omit superfluous pass'),
-    (r'[^\n]\Z', "no trailing newline"),
-    (r'(\S[ \t]+|^[ \t]+)\n', "trailing whitespace"),
-#    (r'^\s+[^_ \n][^_. \n]+_[^_\n]+\s*=',
-#     "don't use underbars in identifiers"),
-    (r'^\s+(self\.)?[A-Za-z][a-z0-9]+[A-Z]\w* = ',
-     "don't use camelcase in identifiers", r'#.*camelcase-required'),
-    (r'^\s*(if|while|def|class|except|try)\s[^[\n]*:\s*[^\\n]#\s]+',
-     "linebreak after :"),
-    (r'class\s[^( \n]+:', "old-style class, use class foo(object)",
-     r'#.*old-style'),
-    (r'class\s[^( \n]+\(\):',
-     "class foo() creates old style object, use class foo(object)",
-     r'#.*old-style'),
-    (r'\b(%s)\(' % '|'.join(k for k in keyword.kwlist
-                            if k not in ('print', 'exec')),
-     "Python keyword is not a function"),
-#    (r'class\s[A-Z][^\(]*\((?!Exception)',
-#     "don't capitalize non-exception classes"),
-#    (r'in range\(', "use xrange"),
-#    (r'^\s*print\s+', "avoid using print in core and extensions"),
-    (r'[\x80-\xff]', "non-ASCII character literal"),
-    (r'("\')\.format\(', "str.format() has no bytes counterpart, use %"),
-    (r'([\(\[][ \t]\S)|(\S[ \t][\)\]])', "gratuitous whitespace in () or []"),
-#    (r'\s\s=', "gratuitous whitespace before ="),
-    (r'[^>< ](\+=|-=|!=|<>|<=|>=|<<=|>>=|%=)\S',
-     "missing whitespace around operator"),
-    (r'[^>< ](\+=|-=|!=|<>|<=|>=|<<=|>>=|%=)\s',
-     "missing whitespace around operator"),
-    (r'\s(\+=|-=|!=|<>|<=|>=|<<=|>>=|%=)\S',
-     "missing whitespace around operator"),
-    (r'[^^+=*/!<>&| %-](\s=|=\s)[^= ]',
-     "wrong whitespace around ="),
-    (r'\([^()]*( =[^=]|[^<>!=]= )',
-     "no whitespace around = for named parameters"),
-    (r'raise [^,(]+, (\([^\)]+\)|[^,\(\)]+)$',
-     "don't use old-style two-argument raise, use Exception(message)"),
-    (r' is\s+(not\s+)?["\'0-9-]', "object comparison with literal"),
-    (r' [=!]=\s+(True|False|None)',
-     "comparison with singleton, use 'is' or 'is not' instead"),
-    (r'^\s*(while|if) [01]:',
-     "use True/False for constant Boolean expression"),
-    (r'^\s*if False(:| +and)', 'Remove code instead of using `if False`'),
-    (r'(?:(?<!def)\s+|\()hasattr\(',
-     'hasattr(foo, bar) is broken on py2, use util.safehasattr(foo, bar) '
-     'instead', r'#.*hasattr-py3-only'),
-    (r'opener\([^)]*\).read\(',
-     "use opener.read() instead"),
-    (r'opener\([^)]*\).write\(',
-     "use opener.write() instead"),
-    (r'(?i)descend[e]nt', "the proper spelling is descendAnt"),
-    (r'\.debug\(\_', "don't mark debug messages for translation"),
-    (r'\.strip\(\)\.split\(\)', "no need to strip before splitting"),
-    (r'^\s*except\s*:', "naked except clause", r'#.*re-raises'),
-    (r'^\s*except\s([^\(,]+|\([^\)]+\))\s*,',
-     'legacy exception syntax; use "as" instead of ","'),
-    (r'release\(.*wlock, .*lock\)', "wrong lock release order"),
-    (r'\bdef\s+__bool__\b', "__bool__ should be __nonzero__ in Python 2"),
-    (r'os\.path\.join\(.*, *(""|\'\')\)',
-     "use pathutil.normasprefix(path) instead of os.path.join(path, '')"),
-    (r'\s0[0-7]+\b', 'legacy octal syntax; use "0o" prefix instead of "0"'),
-    # XXX only catch mutable arguments on the first line of the definition
-    (r'def.*[( ]\w+=\{\}', "don't use mutable default arguments"),
-    (r'\butil\.Abort\b', "directly use error.Abort"),
-    (r'^@(\w*\.)?cachefunc', "module-level @cachefunc is risky, please avoid"),
-    (r'^import Queue', "don't use Queue, use pycompat.queue.Queue + "
-                       "pycompat.queue.Empty"),
-    (r'^import cStringIO', "don't use cStringIO.StringIO, use util.stringio"),
-    (r'^import urllib', "don't use urllib, use util.urlreq/util.urlerr"),
-    (r'^import SocketServer', "don't use SockerServer, use util.socketserver"),
-    (r'^import urlparse', "don't use urlparse, use util.urlreq"),
-    (r'^import xmlrpclib', "don't use xmlrpclib, use util.xmlrpclib"),
-    (r'^import cPickle', "don't use cPickle, use util.pickle"),
-    (r'^import pickle', "don't use pickle, use util.pickle"),
-    (r'^import httplib', "don't use httplib, use util.httplib"),
-    (r'^import BaseHTTPServer', "use util.httpserver instead"),
-    (r'^(from|import) mercurial\.(cext|pure|cffi)',
-     "use mercurial.policy.importmod instead"),
-    (r'\.next\(\)', "don't use .next(), use next(...)"),
-    (r'([a-z]*).revision\(\1\.node\(',
-     "don't convert rev to node before passing to revision(nodeorrev)"),
-    (r'platform\.system\(\)', "don't use platform.system(), use pycompat"),
-
-  ],
-  # warnings
-  [
-  ]
+    [
+        (r'\\$', 'Use () to wrap long lines in Python, not \\'),
+        (
+            r'^\s*def\s*\w+\s*\(.*,\s*\(',
+            "tuple parameter unpacking not available in Python 3+",
+        ),
+        (
+            r'lambda\s*\(.*,.*\)',
+            "tuple parameter unpacking not available in Python 3+",
+        ),
+        (r'(?<!def)\s+(cmp)\(', "cmp is not available in Python 3+"),
+        (r'(?<!\.)\breduce\s*\(.*', "reduce is not available in Python 3+"),
+        (
+            r'\bdict\(.*=',
+            'dict() is different in Py2 and 3 and is slower than {}',
+            'dict-from-generator',
+        ),
+        (r'\.has_key\b', "dict.has_key is not available in Python 3+"),
+        (r'\s<>\s', '<> operator is not available in Python 3+, use !='),
+        (r'^\s*\t', "don't use tabs"),
+        (r'\S;\s*\n', "semicolon"),
+        (r'[^_]_\([ \t\n]*(?:"[^"]+"[ \t\n+]*)+%', "don't use % inside _()"),
+        (r"[^_]_\([ \t\n]*(?:'[^']+'[ \t\n+]*)+%", "don't use % inside _()"),
+        (r'(\w|\)),\w', "missing whitespace after ,"),
+        (r'(\w|\))[+/*\-<>]\w', "missing whitespace in expression"),
+        (r'\w\s=\s\s+\w', "gratuitous whitespace after ="),
+        (
+            (
+                # a line ending with a colon, potentially with trailing comments
+                r':([ \t]*#[^\n]*)?\n'
+                # one that is not a pass and not only a comment
+                r'(?P<indent>[ \t]+)[^#][^\n]+\n'
+                # more lines at the same indent level
+                r'((?P=indent)[^\n]+\n)*'
+                # a pass at the same indent level, which is bogus
+                r'(?P=indent)pass[ \t\n#]'
+            ),
+            'omit superfluous pass',
+        ),
+        (r'[^\n]\Z', "no trailing newline"),
+        (r'(\S[ \t]+|^[ \t]+)\n', "trailing whitespace"),
+        #    (r'^\s+[^_ \n][^_. \n]+_[^_\n]+\s*=',
+        #     "don't use underbars in identifiers"),
+        (
+            r'^\s+(self\.)?[A-Za-z][a-z0-9]+[A-Z]\w* = ',
+            "don't use camelcase in identifiers",
+            r'#.*camelcase-required',
+        ),
+        (
+            r'^\s*(if|while|def|class|except|try)\s[^[\n]*:\s*[^\\n]#\s]+',
+            "linebreak after :",
+        ),
+        (
+            r'class\s[^( \n]+:',
+            "old-style class, use class foo(object)",
+            r'#.*old-style',
+        ),
+        (
+            r'class\s[^( \n]+\(\):',
+            "class foo() creates old style object, use class foo(object)",
+            r'#.*old-style',
+        ),
+        (
+            r'\b(%s)\('
+            % '|'.join(k for k in keyword.kwlist if k not in ('print', 'exec')),
+            "Python keyword is not a function",
+        ),
+        #    (r'class\s[A-Z][^\(]*\((?!Exception)',
+        #     "don't capitalize non-exception classes"),
+        #    (r'in range\(', "use xrange"),
+        #    (r'^\s*print\s+', "avoid using print in core and extensions"),
+        (r'[\x80-\xff]', "non-ASCII character literal"),
+        (r'("\')\.format\(', "str.format() has no bytes counterpart, use %"),
+        (
+            r'([\(\[][ \t]\S)|(\S[ \t][\)\]])',
+            "gratuitous whitespace in () or []",
+        ),
+        #    (r'\s\s=', "gratuitous whitespace before ="),
+        (
+            r'[^>< ](\+=|-=|!=|<>|<=|>=|<<=|>>=|%=)\S',
+            "missing whitespace around operator",
+        ),
+        (
+            r'[^>< ](\+=|-=|!=|<>|<=|>=|<<=|>>=|%=)\s',
+            "missing whitespace around operator",
+        ),
+        (
+            r'\s(\+=|-=|!=|<>|<=|>=|<<=|>>=|%=)\S',
+            "missing whitespace around operator",
+        ),
+        (r'[^^+=*/!<>&| %-](\s=|=\s)[^= ]', "wrong whitespace around ="),
+        (
+            r'\([^()]*( =[^=]|[^<>!=]= )',
+            "no whitespace around = for named parameters",
+        ),
+        (
+            r'raise [^,(]+, (\([^\)]+\)|[^,\(\)]+)$',
+            "don't use old-style two-argument raise, use Exception(message)",
+        ),
+        (r' is\s+(not\s+)?["\'0-9-]', "object comparison with literal"),
+        (
+            r' [=!]=\s+(True|False|None)',
+            "comparison with singleton, use 'is' or 'is not' instead",
+        ),
+        (
+            r'^\s*(while|if) [01]:',
+            "use True/False for constant Boolean expression",
+        ),
+        (r'^\s*if False(:| +and)', 'Remove code instead of using `if False`'),
+        (
+            r'(?:(?<!def)\s+|\()hasattr\(',
+            'hasattr(foo, bar) is broken on py2, use util.safehasattr(foo, bar) '
+            'instead',
+            r'#.*hasattr-py3-only',
+        ),
+        (r'opener\([^)]*\).read\(', "use opener.read() instead"),
+        (r'opener\([^)]*\).write\(', "use opener.write() instead"),
+        (r'(?i)descend[e]nt', "the proper spelling is descendAnt"),
+        (r'\.debug\(\_', "don't mark debug messages for translation"),
+        (r'\.strip\(\)\.split\(\)', "no need to strip before splitting"),
+        (r'^\s*except\s*:', "naked except clause", r'#.*re-raises'),
+        (
+            r'^\s*except\s([^\(,]+|\([^\)]+\))\s*,',
+            'legacy exception syntax; use "as" instead of ","',
+        ),
+        (r'release\(.*wlock, .*lock\)', "wrong lock release order"),
+        (r'\bdef\s+__bool__\b', "__bool__ should be __nonzero__ in Python 2"),
+        (
+            r'os\.path\.join\(.*, *(""|\'\')\)',
+            "use pathutil.normasprefix(path) instead of os.path.join(path, '')",
+        ),
+        (r'\s0[0-7]+\b', 'legacy octal syntax; use "0o" prefix instead of "0"'),
+        # XXX only catch mutable arguments on the first line of the definition
+        (r'def.*[( ]\w+=\{\}', "don't use mutable default arguments"),
+        (r'\butil\.Abort\b', "directly use error.Abort"),
+        (
+            r'^@(\w*\.)?cachefunc',
+            "module-level @cachefunc is risky, please avoid",
+        ),
+        (
+            r'^import Queue',
+            "don't use Queue, use pycompat.queue.Queue + "
+            "pycompat.queue.Empty",
+        ),
+        (
+            r'^import cStringIO',
+            "don't use cStringIO.StringIO, use util.stringio",
+        ),
+        (r'^import urllib', "don't use urllib, use util.urlreq/util.urlerr"),
+        (
+            r'^import SocketServer',
+            "don't use SockerServer, use util.socketserver",
+        ),
+        (r'^import urlparse', "don't use urlparse, use util.urlreq"),
+        (r'^import xmlrpclib', "don't use xmlrpclib, use util.xmlrpclib"),
+        (r'^import cPickle', "don't use cPickle, use util.pickle"),
+        (r'^import pickle', "don't use pickle, use util.pickle"),
+        (r'^import httplib', "don't use httplib, use util.httplib"),
+        (r'^import BaseHTTPServer', "use util.httpserver instead"),
+        (
+            r'^(from|import) mercurial\.(cext|pure|cffi)',
+            "use mercurial.policy.importmod instead",
+        ),
+        (r'\.next\(\)', "don't use .next(), use next(...)"),
+        (
+            r'([a-z]*).revision\(\1\.node\(',
+            "don't convert rev to node before passing to revision(nodeorrev)",
+        ),
+        (r'platform\.system\(\)', "don't use platform.system(), use pycompat"),
+    ],
+    # warnings
+    [],
 ]
 
 # patterns to check normal *.py files
 pypats = [
-  [
-    # Ideally, these should be placed in "commonpypats" for
-    # consistency of coding rules in Mercurial source tree.
-    # But on the other hand, these are not so seriously required for
-    # python code fragments embedded in test scripts. Fixing test
-    # scripts for these patterns requires many changes, and has less
-    # profit than effort.
-    (r'raise Exception', "don't raise generic exceptions"),
-    (r'[\s\(](open|file)\([^)]*\)\.read\(',
-     "use util.readfile() instead"),
-    (r'[\s\(](open|file)\([^)]*\)\.write\(',
-     "use util.writefile() instead"),
-    (r'^[\s\(]*(open(er)?|file)\([^)]*\)(?!\.close\(\))',
-     "always assign an opened file to a variable, and close it afterwards"),
-    (r'[\s\(](open|file)\([^)]*\)\.(?!close\(\))',
-     "always assign an opened file to a variable, and close it afterwards"),
-    (r':\n(    )*( ){1,3}[^ ]', "must indent 4 spaces"),
-    (r'^import atexit', "don't use atexit, use ui.atexit"),
-
-    # rules depending on implementation of repquote()
-    (r' x+[xpqo%APM][\'"]\n\s+[\'"]x',
-     'string join across lines with no space'),
-    (r'''(?x)ui\.(status|progress|write|note|warn)\(
+    [
+        # Ideally, these should be placed in "commonpypats" for
+        # consistency of coding rules in Mercurial source tree.
+        # But on the other hand, these are not so seriously required for
+        # python code fragments embedded in test scripts. Fixing test
+        # scripts for these patterns requires many changes, and has less
+        # profit than effort.
+        (r'raise Exception', "don't raise generic exceptions"),
+        (r'[\s\(](open|file)\([^)]*\)\.read\(', "use util.readfile() instead"),
+        (
+            r'[\s\(](open|file)\([^)]*\)\.write\(',
+            "use util.writefile() instead",
+        ),
+        (
+            r'^[\s\(]*(open(er)?|file)\([^)]*\)(?!\.close\(\))',
+            "always assign an opened file to a variable, and close it afterwards",
+        ),
+        (
+            r'[\s\(](open|file)\([^)]*\)\.(?!close\(\))',
+            "always assign an opened file to a variable, and close it afterwards",
+        ),
+        (r':\n(    )*( ){1,3}[^ ]', "must indent 4 spaces"),
+        (r'^import atexit', "don't use atexit, use ui.atexit"),
+        # rules depending on implementation of repquote()
+        (
+            r' x+[xpqo%APM][\'"]\n\s+[\'"]x',
+            'string join across lines with no space',
+        ),
+        (
+            r'''(?x)ui\.(status|progress|write|note|warn)\(
          [ \t\n#]*
          (?# any strings/comments might precede a string, which
            # contains translatable message)
@@ -389,51 +518,55 @@
          (?# this regexp can't use [^...] style,
            # because _preparepats forcibly adds "\n" into [^...],
            # even though this regexp wants match it against "\n")''',
-     "missing _() in ui message (use () to hide false-positives)"),
-  ] + commonpypats[0],
-  # warnings
-  [
-    # rules depending on implementation of repquote()
-    (r'(^| )pp +xxxxqq[ \n][^\n]', "add two newlines after '.. note::'"),
-  ] + commonpypats[1]
+            "missing _() in ui message (use () to hide false-positives)",
+        ),
+    ]
+    + commonpypats[0],
+    # warnings
+    [
+        # rules depending on implementation of repquote()
+        (r'(^| )pp +xxxxqq[ \n][^\n]', "add two newlines after '.. note::'"),
+    ]
+    + commonpypats[1],
 ]
 
 # patterns to check *.py for embedded ones in test script
 embeddedpypats = [
-  [
-  ] + commonpypats[0],
-  # warnings
-  [
-  ] + commonpypats[1]
+    [] + commonpypats[0],
+    # warnings
+    [] + commonpypats[1],
 ]
 
 # common filters to convert *.py
 commonpyfilters = [
-    (r"""(?msx)(?P<comment>\#.*?$)|
+    (
+        r"""(?msx)(?P<comment>\#.*?$)|
          ((?P<quote>('''|\"\"\"|(?<!')'(?!')|(?<!")"(?!")))
           (?P<text>(([^\\]|\\.)*?))
-          (?P=quote))""", reppython),
+          (?P=quote))""",
+        reppython,
+    ),
 ]
 
 # filters to convert normal *.py files
-pyfilters = [
-] + commonpyfilters
+pyfilters = [] + commonpyfilters
 
 # non-filter patterns
 pynfpats = [
     [
-    (r'pycompat\.osname\s*[=!]=\s*[\'"]nt[\'"]', "use pycompat.iswindows"),
-    (r'pycompat\.osname\s*[=!]=\s*[\'"]posix[\'"]', "use pycompat.isposix"),
-    (r'pycompat\.sysplatform\s*[!=]=\s*[\'"]darwin[\'"]',
-     "use pycompat.isdarwin"),
+        (r'pycompat\.osname\s*[=!]=\s*[\'"]nt[\'"]', "use pycompat.iswindows"),
+        (r'pycompat\.osname\s*[=!]=\s*[\'"]posix[\'"]', "use pycompat.isposix"),
+        (
+            r'pycompat\.sysplatform\s*[!=]=\s*[\'"]darwin[\'"]',
+            "use pycompat.isdarwin",
+        ),
     ],
     # warnings
     [],
 ]
 
 # filters to convert *.py for embedded ones in test script
-embeddedpyfilters = [
-] + commonpyfilters
+embeddedpyfilters = [] + commonpyfilters
 
 # extension non-filter patterns
 pyextnfpats = [
@@ -445,41 +578,40 @@
 txtfilters = []
 
 txtpats = [
-  [
-    (r'\s$', 'trailing whitespace'),
-    ('.. note::[ \n][^\n]', 'add two newlines after note::')
-  ],
-  []
+    [
+        (r'\s$', 'trailing whitespace'),
+        ('.. note::[ \n][^\n]', 'add two newlines after note::'),
+    ],
+    [],
 ]
 
 cpats = [
-  [
-    (r'//', "don't use //-style comments"),
-    (r'\S\t', "don't use tabs except for indent"),
-    (r'(\S[ \t]+|^[ \t]+)\n', "trailing whitespace"),
-    (r'(while|if|do|for)\(', "use space after while/if/do/for"),
-    (r'return\(', "return is not a function"),
-    (r' ;', "no space before ;"),
-    (r'[^;] \)', "no space before )"),
-    (r'[)][{]', "space between ) and {"),
-    (r'\w+\* \w+', "use int *foo, not int* foo"),
-    (r'\W\([^\)]+\) \w+', "use (int)foo, not (int) foo"),
-    (r'\w+ (\+\+|--)', "use foo++, not foo ++"),
-    (r'\w,\w', "missing whitespace after ,"),
-    (r'^[^#]\w[+/*]\w', "missing whitespace in expression"),
-    (r'\w\s=\s\s+\w', "gratuitous whitespace after ="),
-    (r'^#\s+\w', "use #foo, not # foo"),
-    (r'[^\n]\Z', "no trailing newline"),
-    (r'^\s*#import\b', "use only #include in standard C code"),
-    (r'strcpy\(', "don't use strcpy, use strlcpy or memcpy"),
-    (r'strcat\(', "don't use strcat"),
-
-    # rules depending on implementation of repquote()
-  ],
-  # warnings
-  [
-    # rules depending on implementation of repquote()
-  ]
+    [
+        (r'//', "don't use //-style comments"),
+        (r'\S\t', "don't use tabs except for indent"),
+        (r'(\S[ \t]+|^[ \t]+)\n', "trailing whitespace"),
+        (r'(while|if|do|for)\(', "use space after while/if/do/for"),
+        (r'return\(', "return is not a function"),
+        (r' ;', "no space before ;"),
+        (r'[^;] \)', "no space before )"),
+        (r'[)][{]', "space between ) and {"),
+        (r'\w+\* \w+', "use int *foo, not int* foo"),
+        (r'\W\([^\)]+\) \w+', "use (int)foo, not (int) foo"),
+        (r'\w+ (\+\+|--)', "use foo++, not foo ++"),
+        (r'\w,\w', "missing whitespace after ,"),
+        (r'^[^#]\w[+/*]\w', "missing whitespace in expression"),
+        (r'\w\s=\s\s+\w', "gratuitous whitespace after ="),
+        (r'^#\s+\w', "use #foo, not # foo"),
+        (r'[^\n]\Z', "no trailing newline"),
+        (r'^\s*#import\b', "use only #include in standard C code"),
+        (r'strcpy\(', "don't use strcpy, use strlcpy or memcpy"),
+        (r'strcat\(', "don't use strcat"),
+        # rules depending on implementation of repquote()
+    ],
+    # warnings
+    [
+        # rules depending on implementation of repquote()
+    ],
 ]
 
 cfilters = [
@@ -490,82 +622,109 @@
 ]
 
 inutilpats = [
-  [
-    (r'\bui\.', "don't use ui in util"),
-  ],
-  # warnings
-  []
+    [(r'\bui\.', "don't use ui in util"),],
+    # warnings
+    [],
 ]
 
 inrevlogpats = [
-  [
-    (r'\brepo\.', "don't use repo in revlog"),
-  ],
-  # warnings
-  []
+    [(r'\brepo\.', "don't use repo in revlog"),],
+    # warnings
+    [],
 ]
 
 webtemplatefilters = []
 
 webtemplatepats = [
-  [],
-  [
-    (r'{desc(\|(?!websub|firstline)[^\|]*)+}',
-     'follow desc keyword with either firstline or websub'),
-  ]
+    [],
+    [
+        (
+            r'{desc(\|(?!websub|firstline)[^\|]*)+}',
+            'follow desc keyword with either firstline or websub',
+        ),
+    ],
 ]
 
 allfilesfilters = []
 
 allfilespats = [
-  [
-    (r'(http|https)://[a-zA-Z0-9./]*selenic.com/',
-     'use mercurial-scm.org domain URL'),
-    (r'mercurial@selenic\.com',
-     'use mercurial-scm.org domain for mercurial ML address'),
-    (r'mercurial-devel@selenic\.com',
-     'use mercurial-scm.org domain for mercurial-devel ML address'),
-  ],
-  # warnings
-  [],
+    [
+        (
+            r'(http|https)://[a-zA-Z0-9./]*selenic.com/',
+            'use mercurial-scm.org domain URL',
+        ),
+        (
+            r'mercurial@selenic\.com',
+            'use mercurial-scm.org domain for mercurial ML address',
+        ),
+        (
+            r'mercurial-devel@selenic\.com',
+            'use mercurial-scm.org domain for mercurial-devel ML address',
+        ),
+    ],
+    # warnings
+    [],
 ]
 
 py3pats = [
-  [
-    (r'os\.environ', "use encoding.environ instead (py3)", r'#.*re-exports'),
-    (r'os\.name', "use pycompat.osname instead (py3)"),
-    (r'os\.getcwd', "use encoding.getcwd instead (py3)", r'#.*re-exports'),
-    (r'os\.sep', "use pycompat.ossep instead (py3)"),
-    (r'os\.pathsep', "use pycompat.ospathsep instead (py3)"),
-    (r'os\.altsep', "use pycompat.osaltsep instead (py3)"),
-    (r'sys\.platform', "use pycompat.sysplatform instead (py3)"),
-    (r'getopt\.getopt', "use pycompat.getoptb instead (py3)"),
-    (r'os\.getenv', "use encoding.environ.get instead"),
-    (r'os\.setenv', "modifying the environ dict is not preferred"),
-    (r'(?<!pycompat\.)xrange', "use pycompat.xrange instead (py3)"),
-  ],
-  # warnings
-  [],
+    [
+        (
+            r'os\.environ',
+            "use encoding.environ instead (py3)",
+            r'#.*re-exports',
+        ),
+        (r'os\.name', "use pycompat.osname instead (py3)"),
+        (r'os\.getcwd', "use encoding.getcwd instead (py3)", r'#.*re-exports'),
+        (r'os\.sep', "use pycompat.ossep instead (py3)"),
+        (r'os\.pathsep', "use pycompat.ospathsep instead (py3)"),
+        (r'os\.altsep', "use pycompat.osaltsep instead (py3)"),
+        (r'sys\.platform', "use pycompat.sysplatform instead (py3)"),
+        (r'getopt\.getopt', "use pycompat.getoptb instead (py3)"),
+        (r'os\.getenv', "use encoding.environ.get instead"),
+        (r'os\.setenv', "modifying the environ dict is not preferred"),
+        (r'(?<!pycompat\.)xrange', "use pycompat.xrange instead (py3)"),
+    ],
+    # warnings
+    [],
 ]
 
 checks = [
     ('python', r'.*\.(py|cgi)$', r'^#!.*python', pyfilters, pypats),
     ('python', r'.*\.(py|cgi)$', r'^#!.*python', [], pynfpats),
     ('python', r'.*hgext.*\.py$', '', [], pyextnfpats),
-    ('python 3', r'.*(hgext|mercurial)/(?!demandimport|policy|pycompat).*\.py',
-     '', pyfilters, py3pats),
+    (
+        'python 3',
+        r'.*(hgext|mercurial)/(?!demandimport|policy|pycompat).*\.py',
+        '',
+        pyfilters,
+        py3pats,
+    ),
     ('test script', r'(.*/)?test-[^.~]*$', '', testfilters, testpats),
     ('c', r'.*\.[ch]$', '', cfilters, cpats),
     ('unified test', r'.*\.t$', '', utestfilters, utestpats),
-    ('layering violation repo in revlog', r'mercurial/revlog\.py', '',
-     pyfilters, inrevlogpats),
-    ('layering violation ui in util', r'mercurial/util\.py', '', pyfilters,
-     inutilpats),
+    (
+        'layering violation repo in revlog',
+        r'mercurial/revlog\.py',
+        '',
+        pyfilters,
+        inrevlogpats,
+    ),
+    (
+        'layering violation ui in util',
+        r'mercurial/util\.py',
+        '',
+        pyfilters,
+        inutilpats,
+    ),
     ('txt', r'.*\.txt$', '', txtfilters, txtpats),
-    ('web template', r'mercurial/templates/.*\.tmpl', '',
-     webtemplatefilters, webtemplatepats),
-    ('all except for .po', r'.*(?<!\.po)$', '',
-     allfilesfilters, allfilespats),
+    (
+        'web template',
+        r'mercurial/templates/.*\.tmpl',
+        '',
+        webtemplatefilters,
+        webtemplatepats,
+    ),
+    ('all except for .po', r'.*(?<!\.po)$', '', allfilesfilters, allfilespats),
 ]
 
 # (desc,
@@ -573,10 +732,15 @@
 #  list of patterns to convert target files
 #  list of patterns to detect errors/warnings)
 embeddedchecks = [
-    ('embedded python',
-     testparseutil.pyembedded, embeddedpyfilters, embeddedpypats)
+    (
+        'embedded python',
+        testparseutil.pyembedded,
+        embeddedpyfilters,
+        embeddedpypats,
+    )
 ]
 
+
 def _preparepats():
     def preparefailandwarn(failandwarn):
         for pats in failandwarn:
@@ -605,6 +769,7 @@
             filters = c[-2]
             preparefilters(filters)
 
+
 class norepeatlogger(object):
     def __init__(self):
         self._lastseen = None
@@ -630,8 +795,10 @@
             self._lastseen = msgid
         print(" " + msg)
 
+
 _defaultlogger = norepeatlogger()
 
+
 def getblame(f):
     lines = []
     for l in os.popen('hg annotate -un %s' % f):
@@ -640,8 +807,16 @@
         lines.append((line[1:-1], user, rev))
     return lines
 
-def checkfile(f, logfunc=_defaultlogger.log, maxerr=None, warnings=False,
-              blame=False, debug=False, lineno=True):
+
+def checkfile(
+    f,
+    logfunc=_defaultlogger.log,
+    maxerr=None,
+    warnings=False,
+    blame=False,
+    debug=False,
+    lineno=True,
+):
     """checks style and portability of a given file
 
     :f: filepath
@@ -673,8 +848,9 @@
             print(name, f)
         if not (re.match(match, f) or (magic and re.search(magic, pre))):
             if debug:
-                print("Skipping %s for %s it doesn't match %s" % (
-                       name, match, f))
+                print(
+                    "Skipping %s for %s it doesn't match %s" % (name, match, f)
+                )
             continue
         if "no-" "check-code" in pre:
             # If you're looking at this line, it's because a file has:
@@ -684,16 +860,28 @@
             # spelling, we write it with the expected spelling from
             # tests/test-check-code.t
             print("Skipping %s it has no-che?k-code (glob)" % f)
-            return "Skip" # skip checking this file
+            return "Skip"  # skip checking this file
 
-        fc = _checkfiledata(name, f, pre, filters, pats, context,
-                            logfunc, maxerr, warnings, blame, debug, lineno)
+        fc = _checkfiledata(
+            name,
+            f,
+            pre,
+            filters,
+            pats,
+            context,
+            logfunc,
+            maxerr,
+            warnings,
+            blame,
+            debug,
+            lineno,
+        )
         if fc:
             result = False
 
     if f.endswith('.t') and "no-" "check-code" not in pre:
         if debug:
-            print("Checking embedded code in %s" % (f))
+            print("Checking embedded code in %s" % f)
 
         prelines = pre.splitlines()
         embeddederros = []
@@ -705,9 +893,21 @@
 
             for found in embedded(f, prelines, embeddederros):
                 filename, starts, ends, code = found
-                fc = _checkfiledata(name, f, code, filters, pats, context,
-                                    logfunc, curmaxerr, warnings, blame, debug,
-                                    lineno, offset=starts - 1)
+                fc = _checkfiledata(
+                    name,
+                    f,
+                    code,
+                    filters,
+                    pats,
+                    context,
+                    logfunc,
+                    curmaxerr,
+                    warnings,
+                    blame,
+                    debug,
+                    lineno,
+                    offset=starts - 1,
+                )
                 if fc:
                     result = False
                     if curmaxerr:
@@ -717,9 +917,22 @@
 
     return result
 
-def _checkfiledata(name, f, filedata, filters, pats, context,
-                   logfunc, maxerr, warnings, blame, debug, lineno,
-                   offset=None):
+
+def _checkfiledata(
+    name,
+    f,
+    filedata,
+    filters,
+    pats,
+    context,
+    logfunc,
+    maxerr,
+    warnings,
+    blame,
+    debug,
+    lineno,
+    offset=None,
+):
     """Execute actual error check for file data
 
     :name: of the checking category
@@ -752,10 +965,10 @@
     fc = 0
     pre = post = filedata
 
-    if True: # TODO: get rid of this redundant 'if' block
+    if True:  # TODO: get rid of this redundant 'if' block
         for p, r in filters:
             post = re.sub(p, r, post)
-        nerrs = len(pats[0]) # nerr elements are errors
+        nerrs = len(pats[0])  # nerr elements are errors
         if warnings:
             pats = pats[0] + pats[1]
         else:
@@ -794,8 +1007,10 @@
 
                 if ignore and re.search(ignore, l, re.MULTILINE):
                     if debug:
-                        print("Skipping %s for %s:%s (ignore pattern)" % (
-                            name, f, (n + lineoffset)))
+                        print(
+                            "Skipping %s for %s:%s (ignore pattern)"
+                            % (name, f, (n + lineoffset))
+                        )
                     continue
                 bd = ""
                 if blame:
@@ -830,21 +1045,38 @@
 
     return fc
 
+
 def main():
     parser = optparse.OptionParser("%prog [options] [files | -]")
-    parser.add_option("-w", "--warnings", action="store_true",
-                      help="include warning-level checks")
-    parser.add_option("-p", "--per-file", type="int",
-                      help="max warnings per file")
-    parser.add_option("-b", "--blame", action="store_true",
-                      help="use annotate to generate blame info")
-    parser.add_option("", "--debug", action="store_true",
-                      help="show debug information")
-    parser.add_option("", "--nolineno", action="store_false",
-                      dest='lineno', help="don't show line numbers")
+    parser.add_option(
+        "-w",
+        "--warnings",
+        action="store_true",
+        help="include warning-level checks",
+    )
+    parser.add_option(
+        "-p", "--per-file", type="int", help="max warnings per file"
+    )
+    parser.add_option(
+        "-b",
+        "--blame",
+        action="store_true",
+        help="use annotate to generate blame info",
+    )
+    parser.add_option(
+        "", "--debug", action="store_true", help="show debug information"
+    )
+    parser.add_option(
+        "",
+        "--nolineno",
+        action="store_false",
+        dest='lineno',
+        help="don't show line numbers",
+    )
 
-    parser.set_defaults(per_file=15, warnings=False, blame=False, debug=False,
-                        lineno=True)
+    parser.set_defaults(
+        per_file=15, warnings=False, blame=False, debug=False, lineno=True
+    )
     (options, args) = parser.parse_args()
 
     if len(args) == 0:
@@ -859,11 +1091,17 @@
 
     ret = 0
     for f in check:
-        if not checkfile(f, maxerr=options.per_file, warnings=options.warnings,
-                         blame=options.blame, debug=options.debug,
-                         lineno=options.lineno):
+        if not checkfile(
+            f,
+            maxerr=options.per_file,
+            warnings=options.warnings,
+            blame=options.blame,
+            debug=options.debug,
+            lineno=options.lineno,
+        ):
             ret = 1
     return ret
 
+
 if __name__ == "__main__":
     sys.exit(main())